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By A. J. Harrison

"The introduction of an amendment to the Mines Regulation Act in the Province of British Columbia, passed in July 1974, and similar amendments since enacted by other provinces introduced the Canadian underground mining industry to the use of fire-resistant hydraulic fluids.Few, if any, of the hydraulic circuits in use in underground mining at that time were specifically designed for use with fire-resistant fluids, compared with the increasing number of such circuits conceived and in production today. The technology required in designing equipment for use with fire-resistant fluids may be likened to that associated with conventional mineral oils, but, in many respects, a variety of additional and / or alternative considerations must be taken into account. The fast-increasing use and development of fire-resistant fluids throughout all facets of industry, world wide, during the past 20 years has led to a whole new technology in system construction and component design, whereby acceptable performance can be achieved . However , the transition from conventional mineral hydraulic oils has not been without its problems, particularly when retro-fit of existing units was involved."

Jan 1, 1981

By L. Bloomquist

This paper describes how Automated Mining Systems (AMS) is evolving the state-of-the-art in guidance systems for autonomous underground vehicles. The techniques, trade-offs, and lessons learned from these systems are described, including the safety regime that has been implemented. First generation autonomous guidance systems for underground vehicles relied on infrastructure for the vehicle to follow. However, there are additional costs associated with that approach. The current generation uses a pair of laser range finders as its only guidance sensors. This system uses a minimum of infrastructure, in the form of a redundant system of location referencing. Advanced steering and drive control algorithms are incorporated into this generation of system. The next generation of infrastructureless guidance systems will be based on a 3D vision sensor, which was originally developed for autonomous Mars rovers and is being adapted for underground mining use. Results of early underground field trials are presented, along with a description of this emerging technology.

Jan 1, 2004

By Rocky (Yaokun) Wu

This paper introduces the development and application of a new cable anchor - Cable-Lok for pre-stressed cable bolting in mines. Cable-Lok is a spring-loaded cable anchor suitable for the drill hole diameter of 50 and 65 mm (2" and 2.5") in medium soft rock to hard rocks. The cable anchor is automatically set on installation and the cable can be tensioned immediately to provide active and primary support throughout its length. Post-grouting can be conducted independently. In comparison with the conventional cable bolting, Cable-Lok anchor will greatly speed-up the cable bolting circle and decreases the cost of cable bolting. Cable bolting anchored with Cable-Lok anchor has wide application in mines, e.g. pre-stressed cable bolting in large span drifts and intersections for permanent rock support, or in hanging walls or stopes for temporary support, or cable lace anchoring etc. This paper introduces the principle of pre-stressed cable bolting and the specifications of the Cable-Lok anchor, presented the testing results in laboratory and the application cases in mines.

Oct 1, 2010

By A. C. Munro

The concrete work on the new Britannia mill was started in April, 1922. The erection of steel commenced on July 10th, following. The installation of wood work and machinery , began on November 4th of the same year and was pushed to completion in January, 1923. The new mill building is an all steel structure enclosed with galvanized corrugated steel. All main floors and foundations are of reinforced concrete, which makes the building practically fireproof throughout. The mill building rises on a steep hillside to a vertical elevation of 210 feet and has seven distinct floors, for the various opera-tions. Only one elevator, with 30-foot centres, is used in the entire mill. The building is exceptionally roomy and well lighted, both by day and night. The capacity of the mill, as originally designed, was to be 2000 tons daily, but this tonnage can be readily increased to over 3000 tons daily by making slight changes in the fine grinding equipment; in fact, an average of 2700 tons per 24 hours was maintained throughout the month of September.

Jan 1, 1923

By W. B. Xie

The hardening behaviour and microstructure evolution of Cu-30Ni-30Mn alloys aged at 350 °C has been investigated utilizing optical microscope, scanning electron microscope, transmission electron microscopy and Vickers hardness tester. The results show that the discontinuous precipitation of NiMn phase results in a remarkably hardening effect in Cu-30Ni-30Mn alloy during aging at 350 °C. The maximum hardness (~494HV) is attained in the sample after aged for 48 h. The NiMn precipitates are ordered and have a face-centered tetragonal structure. The coherent orientation relationship between the NiMn precipitates and Cu matrix is (220)Matrix // (220)P, [1-1-2]Matrix // [1-1-2]P. In addition, there is a linear relationship between hardness and volume fraction of the discontinuous precipitation, which indicates that the hardness increment of Cu-Ni-Mn alloys aged at 350 °C is attributed to the microstructure characteristics of discontinuous precipitation. The high strength of discontinuous precipitation colony is caused by the formation of nanoscale NiMn precipitates with a lamellar structure in discontinuous precipitation. INTRODUCTION Cu-Ni-Mn alloys are attractive candidates for oil drilling, aerospace and energy applications due to their high elasticity, high strength and excellent corrosion resistance (Sun et al., 2009; Liu, Yang, Xia, Jiang, & Gui, 2016). The high strength of the Cu-Ni-Mn alloys is mainly attributed to the precipitation of NiMn phase (Shapiro, Tyler, & Lanam, 1974; Xie et al., 2015). The uniformly dispersed nanoprecipitates formed by continuous precipitation can impede dislocation movement, and thereby lead to a significant improvement in strength of traditional precipitation-strengthened alloys. However, it is reported that there are two precipitation types observed in Cu-Ni-Mn alloys, namely, continuous precipitation and discontinuous precipitation (Shapiro et al., 1974). The discontinuous cellular colony with a lamellar structure nucleates at grain boundaries, and progressively grows inward the grain on the process of discontinuous precipitation (Ng, Bettles, & Muddle, 2011). It is found that the discontinuous precipitation can occur in many Cu-based alloys, such as Cu-Ni- Mn alloy (Shapiro et al., 1974), Cu-Be alloy (Monzen, Hasegawa, & Watanabe, 2010) and Cu-Ni-Sn alloy (Zhao, & Notis, 1998). Many studies consider that the discontinuous precipitation results in a detrimental effect on hardness and strength, and the discontinuous precipitation occurring during aging treatment should be suppressed (Markandeya, Nagarjuna, & Sarma, 2004; Semboshi, Sato, Iwase, & Takasugi, 2016). The mechanical properties can also be improved by discontinuous precipitation in AZ91 magnesium alloy (Tamura, Kida, Suzuki, & Soda, 2009) and AM30 magnesium alloy (Saikawa et al., 2012). Jun (2017) found that the reduced interlamellar spacing of precipitate fibers in discontinuous cellular colony leads to a significant increase in hardness. Indeed, the strengthening contribution of discontinuous precipitation is similar to that of continuous precipitation in Cu-20Ni-20Mn alloy. Discontinuous precipitation of NiMn phase can provide a significant strengthening effect in Cu-Ni-Mn alloys.

Jan 1, 2019

By Brock Morrison, Bernt Ling

"The Kiruna Electric System is an all electric ramp haulage system developed for underground mining. This electric truck haulage system is currently operating on three continents. This paper will review the technology of the system, existing installations as well as the economical benefits to the mining industry. The system was designed and developed to extend and exploit the economical advantages of ramp haulage. Performance information is provided. IntroductionThe Kiruna Electric System has been the subject of a number of technical papers over the past sever al years. During that period, the content of the presentations has changed from concept and theory to prototype testing to description of installed and operating systems.The intent of this paper is threefold:1. to present a brief review of the technical features of the Kiruna Electric Systems;2. to review the existing installations with performance data; and3. to provide a description of on-going developments within the Kiruna Electric Program during 1991.The Kiruna Electric is a high capacity ramp haulage system for underground mining operations due to an All-Electric Drive System, including two heavy duty electric traction motors. The high capacity of the K1050E results from three factors:• payload - 50 tonne• speed - 18 km/hr to 20 km/hr up a IS0J0 ramp (total resistance)• availability - over 90010 during a 12-month period"

Jan 1, 1991

By Y. M. Jubeli

"Abstract - Gamma-ray spectrometry, an effective tool in geological mapping, was used to define boundaries between various lithological formations in three adjacent areas of Central Syria, namely, the Syrian Desert, Ar Rassafeh Badiayat and the Northern Palmyrides mountains. This paper describes the role of an airborne gamma spectrometric survey which was orginally undertaken to assist uranium exploration. Interpretation of the total count data obtained through the survey has led to significant modifications and corrections to the previously published distribution map of the palaeogene phosphate rocks.Another important result of the survey is the discovery of four previously unknown phosphorite horizons in the Rasm Al-Aawabed area of the Northern Palmyrides. In addition, previously unknown phosphatic horizons are outlined in the other study areas. The importance of this technique as an effective prospecting method, not only for U but also for exploring for the economically important phosphorite formations in Syria, is emphasized. Furthermore, its role in geological mapping is stressed, especially in areas that lack sufficient geological data."

Jan 1, 1997

By L. Bloomquist, C. Arnoldi

"This paper describes how Automated Mining Systems (AMS) is evolving the state-of the- art in guidance systems for autonomous underground vehicles. The techniques, tradeoffs, and lessons learned from these systems are described, including the safety regime that has been implemented.First generation autonomous guidance systems for underground vehicles relied on infrastructure for the vehicle to follow. However, there are additional costs associated with that approach.The current generation uses a pair of laser range finders as its only guidance sensors. This system uses a minimum of infrastructure, in the form of a redundant system of location referencing. Advanced steering and drive control algorithms are incorporated into this generation of system.The next generation of infrastructureless guidance systems will be based on a 3D vision sensor, which was originally developed for autonomous Mars rovers and is being adapted for underground mining use. Results of early underground field trials are presented, along with a description of this emerging technology."

Jan 1, 2004

By K. Szafran, R. E. L. Seal, M. Tansey

Conversion of hydraulic equipment to fire resistant fluids has been hampered by less than satisfactory component performance and in some cases, catastrophic equipment failure. Concern over identifying possible causes to these problems led to a joint research project between the Potash Corporation of Saskatchewan Mining Limited and the University of Saskatchewan. This paper summarizes some of the results and conclusions derived from this joint project. In this study, the research was limited to evaluating the effects of potash contamination on the performance of hydraulic equipment. Two separate types of tests were conducted in order to provide a basis upon which trends could be established. This study concluded that the presence of potash dust in the hydraulic fluid can induce severe wear over relatively short periods of time. It was also deduced that a contaminant free fluid combined with proper fluid maintenance could extend the performance of hydraulic components using fire resistant fluids even under very severe operating conditions, such as elevated pressures and temperatures. Recommendations as to how to achieve this goal and the practicality of doing so are presented.

Jan 1, 1988

Scope / Agenda ? What is Situation Awareness (SA)? ? Background on SA theory ? SA is critical in a wide variety of domains ? SA and human performance ? Consequences of poor SA ? Significant challenges for SA in mining operations ? Technology centric design ? SA-oriented design methodology ? Goal-Directed Task Analysis ? Design ? SA Measurement and Evaluation ? Applications of SA-oriented design

Aug 1, 2013

By C. M. Díaz, P. J. Mackey, P. Coursol

In a recent paper [1], the present authors discussed calculated energy consumption numbers in copper sulphide concentrate smelting for four different smelting technologies. For the present study, from among these technologies, they selected the Noranda/Teniente continuous bath smelting followed by Peirce Smith (PS) converting route to investigate the impact on total energy requirement of some key process variations, such as tuyere injection of dry concentrate vs. slingering of wet concentrate over the molten bath, continuous converting vs. conventional batch PS converting and commercially proven slag cleaning alternatives. In their calculations, the authors used the same thermochemical model and methodology used in their earlier paper. This approach to explore plant design options provides an interesting basis for evaluating flowsheet modifications that could lead to significant copper smelting energy savings. The METSIM software was used in the present paper to carry out heat and mass balance computations for 8 different flowsheet configurations. The results are presented and discussed in the paper with respect to copper recoveries, energy requirements and CO2 emissions.

Jan 1, 2011

By G. G. Bowser

Introduction Flame shots are of very infrequent occurrence in the coal mines of Nova Scotia. Probably not more than one is recorded in three months. Many shot-firers have never experienced one, and many never will. As a consequence, although all such occurrences are very carefully investigated, information concerning the cause of flame shots is somewhat meagre. In the course of the years, however, something has been learned of the practices and conditions that are responsible for them. During the past ten? years, over seventeen million shots were fired in the coal mines of Nova Scotia and only fifty-two faulty shots were reported or investigated during that time. In thirty-nine of these, flames were reported; in five, sparks only; and in eight, smoke only. In eight of these occurrences, unburned explosive was found after firing. In one of these eight, flame was seen in the back part of the hole, and an accompanying hissing sound pointed to burning explosive. In four of them, there was no evidence that gas was not ignited. All samples of explosives from these faulty shots which were submitted for analysis were found to be normal, except two, in 1937, which contained excessive moisture. These two samples were from two following shots in the same room on the same day. The initial cause of trouble with all eight shots was one or several of the following: explosives in poor condition, separation of cartridges, incorrect priming, shot hole in poor condition or not properly cleaned. In the case of sixteen or seventeen of the thirty-nine shots which flamed, data are insufficient for conclusions to be drawn as to the cause of the flame.

Jan 1, 1947

By M. L. F. Paullo, S. Cristian Mejia, D. Roehl

"Rock fracture simulation most often presents non-linear behaviour due to loss of material integrity and strain concentration in the fracture zone. These strains generate local instabilities that propagate to the global system of equilibrium equations, generating convergence problems of the numerical solution. Often, in such cases, analyses in the post-critical regime are unfeasible. To overcome the numerical difficulties associated with problems of stiffness loss in the post-critical regime control methods, also called continuation methods, are employed. Among them are the arc-length method, the energy control method and the indirect displacement control method. These methods are employed in conjunction with a Newton- Raphson scheme for the solution of non-linear systems of equations. However, depending on the system instability, convergence in not guaranteed even with very small increments. In the present work these control techniques are investigated in combination with cohesive elements to simulate rock fracture. The constitutive model employed with the cohesive elements represents stiffness degradation through a damage law, which leads to serious convergence difficulties as reported in the literature. Here the continuation methods mentioned are applied to a Mode I rock fracture problem and to hydraulic fracture simulations. The effectiveness of the different continuation methods is compared.INTRODUCTIONThe process of rock fracture induced by the fluid pressure is called hydraulic fracturing. The propagation of a hydraulic fracture is a complex process, which is basically defined by the mechanical deformation of the rock, the fluid flow within the fracture and the fracture propagation itself (Mokryakov, 2011). In the works of Bendezu et al. (2013), Chen (2012) and Carrier et al. (2012), vertical hydraulic fracture propagation is modeled by cohesive elements with traction-separation law. The softening behavior of rock in post-critical regime is demonstrated by experimental testing and is characterized mainly by high strains and low stresses (Crowder and Bawden, 2004). This nonlinear behaviour can arise due to material nonlinearity, such as micro-cracking and damage, leading to softening behaviour (Chandrakant, S.D., 2012). The cohesive fracture model considers in its formulation the softening behaviour that most rocks present in post-critical regime with propagation criteria."

Jan 1, 2015

By Y. M. Jubeli

"Gamma-ray spectrometry, an effective tool in geological mapping, was used to de?ne boundaries between various lithological formations in three adjacent areas of Central Syria, namely, the Syrian Desert, Ar Rassafeh Badiayat and the Northern Palmyrides mountains.This paper describes the role of an airborne gamma spectrometric survey which was originally undertaken to assist uranium exploration. Interpretation of the total count data obtained through the survey has led to signi?cant modi?cations and corrections to the previously published distribution map of the palaeogene phosphate rocks.Another important result of the survey is the discovery of four previously unknown phosphorite horizons in the Rasm Al-Aawabed area of the Northern Palmyrides. In addition, previously unknown phosphatic horizons are outlined in the other study areas. The importance of this technique as an effective prospecting method, not only for U but also for exploring for the economically important phosphorite formations in Syria, is emphasized. Furthermore, its role in geological mapping is stressed, especially in areas that lack suf?cient geological data."

Jan 1, 1997

By Michele L. Kimble

A fast-flow reactor mass spectrometer has been utilized to investigate the reactions of gas-phase gold cluster anions with CO and oxygen. Addition of CO to Aun - produces species of the form Au(CO)m -, where m = 2-5. However, CO does not bind to Au2 - or Au3 -. With oxygen addition in the cluster source, gold oxide species with both molecular and atomized oxygen are produced. The addition of carbon monoxide to these preoxidized gold cluster anions reveals that select species with 1, 2, and 3 gold atoms participate in the oxidation reaction to produce CO2. Bimolecular rate constants for the reactions between these species and CO are also discussed.

Oct 1, 2003

By C. C. Walden, A. Bruynesteyn

"Chemical and biological aspects of the formation of acidic effluents from sulfide waste materials are discussed. Test procedures to determine the acid producing potential of waste materials, as well as the characteristics of such acidic effluents, are presented. Practical applications of the test procedures are discussed with reference to predictior of environmentally unacceptable drainage and to estimation of metal recovery by dump leaching.INTRODUCTIONNatural leaching of sulfide minerals, exposed to the atmosphere, has been occurring for geological time. For centuries, man has been aware of the acid drainage originating from coal workings, copper mines and waste dumps. With the advent of the technical sciences, the processes involved in acid mine drainage production were considered to be solely chemical in nature. However, in 1947, it was shown (1) that a specific microorganism, called Thiobacillus ferrooxidans, was responsible for acid mine drainage from coal workings. It was demonstrated that under suitable conditions - this bacterium oxidized pyrite and marcosite in the coal to ferric sulfate and sulfuric acid. Numerous studies have subsequently demonstrated that - under suitable conditions - Thiobacillus ferrooxidans can attack most sulfide minerals, producing weak sulfuric acid, oxidizing ferrous to ferric iron and solubilizing other metals present (notably copper and zinc) as their sulfate salts."

Jan 1, 1980

By J. T. Chen, S. Winkler, M. J. Worswick, O. Orlov

This paper presents a review of research conducted at the University of Waterloo concerned with the application of aluminum alloy sheet and tube in automotive structures and body panels. The research has focussed on formability prediction and results using a range of damage-based formulations. These models include continuum-level damage approaches and, more recently, a so-called percolation damage approach intended to capture microstructural heterogeneity effects on damage development. This paper presents applications of these damage approaches to simulate formability of experiments considering stretch flange panels. The experiments consider drawbead effects associated with the bend/unbend deformation as the material flows through the drawbead. Recent work on simulating in situ X-ray tomography experiments that capture damage evolution during tensile deformation will also be reviewed.

Jan 1, 2006

By D. Yu, T. A. Utigard, M. Barati

"Sulfation roasting of nickel concentrate to generate water-soluble metal sulfates was investigated as an alternative process to smelting for the recovery of valuable metals. The kinetics of dissolution of various species of the calcine in three leachants was studied; hot water, dilute HCl, and concentrated HCl. The results indicated that dissolution of sulfates by hot water at 90 ºC is achieved within 30 minutes. In order to increase the recovery of the valuable metals, acid leaching is necessary due to the existence of ferrite in the calcine.INTRODUCTIONInvestigations on the sulfation roasting of nickeliferous sulfide ores or concentrates were mainly carried out in 1950’s to 1990’s to generate water soluble non-ferrous metal sulfates followed by metal recovery by leaching (Stephens, 1953; Thornhill, 1954, 1961; Fletcher and Shelef, 1964a, 1964b; Fletcher and Hester, 1964; Frankiewicz, 1977; Norrgran, 1983). Commercialization of the sulfation roasting process was only performed by Falconbridge Ltd. (Thornhill, 1961; Boldt, 1967), which employed a sulfation roast process on nickeliferous pyrrhotite at 680 oC where Ni, Cu, and Co were leached and Fe2O3 was produced for the iron industry. In 1965, 118,342 tons of pyrrhotite was processed, however because of the huge SO2 emissions (no acid plant) relative to the nickel production and the poor economics, this plant was shut down.Nickel production from sulfide ores via pyrometallurgical means, especially the electric furnace smelting process, is a major emitter of SO2 to the environment and a big energy consumer (Warner, Diaz, Dalvi, Mackey, Tarasov and Jones, 2007). Nowadays, due to the more stringent environmental regulations as well as the need to reduce energy consumption, metal production by sulfation roasting is gaining more attention as an alternative process to smelting. The main focus of this paper is to investigate the extent and rate of leaching of valuable metals from the sulfation roasted nickel calcine, aiming to maximize the metal recovery and minimize the dissolution of iron species."

Jan 1, 2012

By G. S. Hume

THE discovery of natural gas with naphtha in 1924 in the Upper Palaeozoic limestone of Turner Valley, 35 miles southwest of Calgary, has led to continuous developments in this field. Drilling undertaken soon after this discovery demonstrated that the anticlinal structure was in reality a major drag-fold cut off on the east side by a westerly inclined fault of large displacement. The faulted edge of the .limestone at depth determines the eastern limits of the field, which between 1924 and 1936 was shown to have a gas area 14 miles long by about 1 mile wide. Since the strata dip westerly, away from the axis of the fold, drilling becomes progressively deeper to the west and, with the advent of deeper drilling, crude oil was discovered in 1936 on the west flank of the structure but in the same porous reservoir rocks as the gas on the crest and upper parts of the fold. Since 1936, drilling has been undertaken wholly for the production of crude-oil and at present two producing areas have been found within the Turner Valley structure. The larger of these, at the south end of the field, in the vicinity of Highwood river, has a length of about 4 3/4 miles and a proved width of one mile, whereas the smaller, in the north end of the field, south of the north fork of Sheep river, has only a few producing wells.

Jan 1, 1939

By F. Habashi

"A short account will be presented on the extraction of rare earths from monazite sand, bastnasite ore, and phosphate rock of igneous origin. This includes mineral beneficiation, leaching methods, fractional crystallization [of historical interest], ion exchange, solvent extraction, precipitation from solution, and reduction to metals. INTRODUCTIONOriginally, the term rare earths was only used for the oxides, R2O3, which are similar to one other in their chemical and physical properties and are therefore difficult to separate. Within the rare earth group, the elements scandium, yttrium, and lanthanum differ in their atomic structure from the elements cerium to lutetium (the lanthanides, Ln). Scandium occupies a special position with respect to this classification and its other properties, and therefore does not belong to either of these groups. The rare earth elements always occur in nature in association with each other. The isolation of groups of rare earth elements or of individual elements requires costly separation and fractionation processes owing to the great similarity of the chemical and physical properties of their compounds, which explains why the history of their discovery has extended over such a long period.The word “rare”, when used to describe this group of elements, originates from the fact it was thought that these elements could only be isolated from very rare minerals. Considering their abundance in the Earth’s crust, the term rare is now inappropriate. These elements are lithophilic and are therefore concentrated in oxidic compounds such as carbonates, silicates, titano-tantalo-niobates, and phosphates.The abundance of the rare earth elements taken together is quite considerable. Cerium, the most common rare earth, is more abundant than cobalt. Yttrium is more abundant than lead, whereas Lu and Tm are as abundant as Sb, Hg, Bi, and Ag. For all practical purposes promethium does not occur in nature. It forms only in nuclear reactors."

Jan 1, 2012